Save your old 18650's

[Angrygod50]

Get enough you can put them to good use.
https://www.youtube.com/watch?time_continue=16&v=Md4l9bFDOtc

 

[The Cromwell]

Why would you want to use worn out batteries to power your house?

Put a bunch of Efests in that power bank and watch the show?

 

[Ryedan]

Get enough you can put them to good use.

Good gawd ...

No ... No ... No

Recycling lithium ion batteries for a project like this is a really bad idea